Protecting a network requires more than a single security tool. In IB Computer Science, students are expected to understand different network security mechanisms and how they work together. Two commonly examined tools are firewalls and intrusion detection systems (IDS). Although both protect networks, they serve very different roles.
IB examiners reward answers that clearly compare prevention vs detection.
What Is a Firewall?
A firewall is a security system that:
- Controls incoming and outgoing network traffic
- Applies predefined rules
- Blocks unauthorised access
Firewalls act as a barrier between:
- Trusted internal networks
- Untrusted external networks
In IB terms, firewalls focus on preventing attacks before they happen.
How Firewalls Work
Firewalls:
- Inspect network traffic
- Allow or block data packets
- Enforce access rules
They are commonly used to:
- Block unauthorised connections
- Restrict access to services
- Protect internal systems
Firewalls operate in real time, stopping traffic at the network boundary.
What Is an Intrusion Detection System (IDS)?
An Intrusion Detection System (IDS) is a security system that:
